Reference Form 裏的問題. - 留學

因為教授叫我自己填Reference Form,
在Form裏出現一條問題:
if you are an academic referee, please indicate the cohort against
whom you are measuring the applicant
(eg:number of students/all students in current year/all students you have ever taught)

不是很懂它的意思, 是要 排名 嗎?
還是要做甚麼 ?

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